A reactor is known that is used for producing polymers and that has a stirring blade and a heat transfer pipe.
For example, Patent Document 1 discloses a reactor that enables mixing in a shorter time as a result of improving a mixing performance by adjusting a shape and arrangement of a stirring blade, and enables cooling in a shorter time as a result of improving a heat removal performance by using a hairpin coil baffle as the heat transfer pipe. According to Patent Document 1, improving the mixing performance of the above described reactor can prevent the occurrence of gelatinous materials resulting from the adhesion of a polymer to vessel walls, coils and the like, and can thus reduce appearance defects, printing defects, and the like of a molded article caused by these gelatinous materials. Furthermore, according to Patent Document 1, as a result of enabling the cooling in a shorter time by improving the heat removal performance, the above described reactor can reduce unexpected deactivation and bonding of an activated terminal, and can stabilize the quality of the produced polymer.